Top 10 international science stories of 2020
申博138游戏直营网,自动化装配线中国一拖拥有6条国内生产能力最强、信息化水平最高的拖拉机装配线；拥有自动化、柔性化程度高的重柴装配线；具有国内最强的拖拉机核心零件制造能力，拥有各类加工设备200余台，技术和装备水平达到国内领先。 尚有27亿存续债券 博源集团原名内蒙古博源投资集团有限公司，由原伊化持股会改制设立而来。而上海上港和上海申花则要参加亚冠资格，但都只需要通过一轮资格赛就能进入亚冠正赛，且均为主场作战。这些人存在，未来六年内，中国真的能跨过“中等收入陷阱”？但《大国大城：当代中国的统一、发展与平衡》的作者陆铭认为，中国跨过中等收入陷阱，进入高收入国家，并不存在障碍。
From the rapid development of COVID-19 vaccines to DeepMind's new AI solution AlphaFold, here is a round-up of some of the most important scientific advances of 2020.
# Record-breaking COVID-19 vaccine development
As of Dec. 29, 2020, there were more than 200 vaccine candidates (60 in clinical and 172 in preclinical development) under development around the globe, according to the World Health Organization.
A team led by Dr. Kathrin Jansen, head of vaccine research at U.S. pharmaceutical company Pfizer, delivered a clinically validated vaccine in record time. Meanwhile, an adenovirus vector vaccine developed by a research team led by Chen Wei, an academician with the Chinese Academy of Engineering and a researcher at the Institute of Military Medicine under the Academy of Military Sciences, was the first COVID-19 vaccine in the world to enter phase 2 clinical trials, bringing much hope to the world.
# A 'shocking' step toward a potential HIV cure
"Shock and kill" is a leading research strategy for eliminating HIV from the body, and refers to activating the dormant virus from within immune cells where it hides, and then eliminating it. One obstacle so far has been finding a safe way to "wake up" the virus.
In January 2020, researchers reported in two complementary Nature papers that they have come closer to that goal. The papers rely on studies involving two animal models of HIV infection. Despite taking different approaches, the studies both yielded promising results, disrupting viral latency at levels not seen before.
In simple terms, the virus was brought out of its hiding places, even in the presence of antiretroviral drugs that had prevented it from replicating for several months.
The findings do not yet represent a cure, while follow-up studies in animals, as well as clinical trials in humans, are still needed and planned. However, the results represent an important advance as they could potentially be combined with other approaches directed against the virus.
# Strongest evidence yet that neutrinos can explain the origins of the universe
Scientists are a step closer to determining whether neutrinos and antineutrinos behave differently, potentially solving a key question about the universe's creation.
In 2020, the T2K Collaboration in Japan published new results showing the strongest constraint yet on the parameter that governs the breaking of the symmetry between matter and antimatter in neutrino oscillations.
After a decade of firing trillions of protons at their target every second, T2K researchers had tallied just 90 electron neutrinos and 15 electron antineutrinos. The counts were big enough for the group to reach a tantalizing conclusion. Muon neutrinos turn into electron neutrinos at a higher rate than muon antineutrinos turn into electron antineutrinos, the 357-strong team reported in scientific journal Nature on April 16, 2020.
# Largest-known public catalogue of genetic variants in humans unveiled
The function of most genes in the human genome remains unknown. One way of discovering a gene's function to observe what happens when it is disrupted by a mutation. These variants often have adverse outcomes and are usually rare. Large genetic sequencing studies provide an opportunity to examine the effects of these loss-of-function variants, which could provide important insights into human biology and diseases.
This year, the scientific journals Nature, Nature Communications, and Nature Medicine, published the results of the latest effort: a catalogue of 443,769 predicted loss-of-function variants in 125,748 whole-exome and 15,708 whole-genome sequencing datasets, collected from samples from more than 140,000 people.
The results, compiled in the Genome Aggregation Database (gnomAD), are the most extensive publicly accessible analysis carried out so far, and will help researchers better understand the functions of genes and roots of genetic disorders as well as how to treat them.
# Elon Musk announces Neuralink's 'brain-machine interface'
In late August 2020, Elon Musk held a press conference on Neuralink, a brain-machine interface start-up, where he used the "three little pigs" to demonstrate the company's neuron-reading brain implant.
One of the pigs has had a coin-sized computer chip in its brain for two months. A screen above the pig streamed the electrical brain activity being registered by the device. This move demonstrates an early step toward the goal of curing human diseases with similar types of implant.
Founded in 2016, Neuralink aims to implant wireless brain-computer interfaces composed of thousands of electrodes in the most complex human organ to help cure neurological conditions such as Alzheimer's, dementia and spinal cord injuries and ultimately fuse humankind with artificial intelligence.
# Room-temperature superconductivity achieved for first time
The first superconductor discovered in 1911 had an extremely low critical temperature, only a few degrees above absolute zero. Ever since this discovery, scientists have dreamt of room-temperature superconductivity.
Superconductors transmit electricity without resistance, allowing current to flow without any energy loss. However, all superconductors previously discovered must be cooled, many of them to very low temperatures, making them impractical for most uses.
In October 2020, a team of American scientists found the first superconductor that operates at room temperature. The material made of carbon, sulfur and hydrogen is superconductive below temperatures of about 15 degrees Celsius.
Hydrogen-rich materials under high pressure have been shown to increase the temperatures at which superconductivity can be demonstrated, to around minus 23 degrees Celsius. The latest work raises the temperature at which a zero-resistance state is achieved to 15 degrees Celsius. This effect is observed in a photochemically synthesized ternary carbonaceous sulfur hydride system at pressures of 267 billion pascals.
While the material superconducts under only high pressures, the breakthrough brings scientists a step closer to realizing a more energy-efficient future.
# A fast radio burst first reveals its origins
Fast radio bursts, or FRBs, are bright, powerful emissions of radio waves ranging from a fraction of a millisecond to a few milliseconds. Since they were first discovered in 2007, astronomers from around the world have used radio telescopes to trace the bursts and look for clues about where they come from and how they are produced.
According to studies published in the journal Nature in November 2020, researchers tracked a fast radio burst to a type of star called a magnetar that is 32,000 light-years from earth. This was not only the first FRB traced to its source, but the first to emanate from our galaxy.
Back in April, an international team led by scientists at the National Astronomical Observatories of the Chinese Academy of Sciences (NAOC) made the discovery by analyzing data from China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST). Radio observatories in Canada and the United States also caught a glancing blow from an FRB.
# AlphaFold makes its mark in predicting protein structures
DeepMind has developed an artificial intelligence solution to a 50-year-old protein challenge: predicting how proteins curl up from a linear chain of amino acids into 3D shapes that allow them to carry out life's tasks.
The human body uses tens of thousands of different proteins, each a string of dozens to many hundreds of amino acids. The order of those amino acids dictates how the myriad pushes and pulls between them give rise to proteins' complex 3D shapes, which in turn determine how they function.
For decades, researchers deciphered proteins' 3D structures using experimental techniques such as X-ray crystallography or cryo-electron microscopy (cryo-EM). However, such methods can take months or years and do not always work. Structures have been solved for only about 170,000 of the more than 200 million proteins discovered across life-forms.
In November 2020, DeepMind's AlphaFold won the 14th Community Wide Experiment on Critical Assessment of Techniques for Protein Structure Prediction (CASP14), a biennial competition in which entrants receive amino acid sequences for about 100 proteins whose 3D structures are unknown. By comparing the computational predictions with the lab results, each CASP14 competitor received a global distance test (GDT) score.
Across target proteins in this year's CASP, AlphaFold achieved a median GDT score of 92.4. For the most challenging proteins, AlphaFold scored a median of 87, which was 25 points above the next best predictions. It even excelled at solving structures of proteins that sit wedged in cell membranes, which are central to many human diseases but notoriously difficult to solve with X-ray crystallography.
This progress marks a significant step forward for scientists, who will be able to use accurate structure predictions to make sense of opaque X-ray and cryo-EM data. It could also enable drug designers to quickly ascertain the structure of every protein in new and dangerous pathogens like the coronavirus to speed up the creation of new medications.
# CRISPR successfully fixes cell defects in two blood disorders
The gene-editing tool CRISPR scored its first success in clinical trials by treating two inherited blood diseases.
Beta thalassaemia and sickle cell disease are conditions caused by mutations that affect hemoglobin, the protein that carries oxygen in red blood cells.
Two people with beta thalassaemia and one with sickle cell disease no longer require blood transfusions — which are normally used to treat severe forms of these inherited diseases — after their bone marrow stem cells were gene-edited with CRISPR.
The patients, after been treated for 17 months, are now making plentiful fetal hemoglobin, and have not experienced the painful attacks that used to strike every few months, according to reports by CRISPR Therapeutics and Vertex Pharmaceuticals in December.
# China's Chang'e-5 mission
On Dec. 19, 2020, approximately 1,731 grams of samples from the moon were retrieved from the Chang'e-5 probe. Since then, the storage, analysis and research work of the lunar samples has been carried out accordingly.
The sixth mission in the Chang'e program, Chang'e-5, was one of the most difficult and challenging endeavors China has ever embarked on.
The probe achieved four significant "firsts" in Chinese space exploration: the automatic sampling of the lunar surface by probe; the first take-off from the moon's surface; the first unmanned rendezvous and docking in lunar orbit around 380,000 km away; and the first high-speed return to earth with lunar soil samples.
The entire world has been following the Chang'e 5 mission closely. According to journal Science: "The capsule's return marks the first time China has collected rocks from the Moon — and the first time any nation has accomplished the feat since 1976."（You can also read it at：申博138游戏直营网/www_china_org_cn/top10/2021-01/20/content_77130717_10.htm）